Fix nova-compute start failed when reserved_huge_pages has value.

The problem is due to this change:
https://review.openstack.org/#/c/292499/20/nova/conf/virt.py

The code of item_type=types.Dict is not correct, modfiy by
item_type=types.Dict().

Modify the usage discription of config of reserved_huge_pages.
Usage of oslo_config.types.Dict is key:value pairs separated by
commas.

Add unit test because this is a complicated option that might not work
like people expect.

Closes-Bug:#1588305
Change-Id: I06490866f24617cf99764ede73a1938c2d7b7b5c

1 files changed, 82 insertions, 0 deletions

diff --git a/nova/tests/unit/test_conf.py b/nova/tests/unit/test_conf.py
new file mode 100644
index 0000000000..17f3630cea
--- /dev/null
+++ b/nova/tests/unit/test_conf.py
@@ -0,0 +1,82 @@
+# Copyright 2016 HPE, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import os
+import tempfile
+
+import fixtures
+from oslo_config import cfg
+
+import nova.conf.virt
+from nova import test
+
+
+class ConfTest(test.NoDBTestCase):
+    """This is a test and pattern for parsing tricky options."""
+
+    class TestConfigOpts(cfg.ConfigOpts):
+        def __call__(self, args=None, default_config_files=None):
+            if default_config_files is None:
+                default_config_files = []
+            return cfg.ConfigOpts.__call__(
+                self,
+                args=args,
+                prog='test',
+                version='1.0',
+                usage='%(prog)s FOO BAR',
+                default_config_files=default_config_files,
+                validate_default_values=True)
+
+    def setUp(self):
+        super(ConfTest, self).setUp()
+        self.useFixture(fixtures.NestedTempfile())
+        self.conf = self.TestConfigOpts()
+        self.tempdirs = []
+
+    def create_tempfiles(self, files, ext='.conf'):
+        tempfiles = []
+        for (basename, contents) in files:
+            if not os.path.isabs(basename):
+                (fd, path) = tempfile.mkstemp(prefix=basename, suffix=ext)
+            else:
+                path = basename + ext
+                fd = os.open(path, os.O_CREAT | os.O_WRONLY)
+            tempfiles.append(path)
+            try:
+                os.write(fd, contents.encode('utf-8'))
+            finally:
+                os.close(fd)
+        return tempfiles
+
+    def test_reserved_huge_page(self):
+        nova.conf.virt.register_opts(self.conf)
+
+        paths = self.create_tempfiles(
+            [('1',
+              '[DEFAULT]\n'
+              'reserved_huge_pages = node:0,size:2048,count:64\n')])
+        self.conf(['--config-file', paths[0]])
+        # NOTE(sdague): In oslo.config if you specify a parameter
+        # incorrectly, it silently drops it from the conf. Which means
+        # the attr doesn't exist at all. The first attr test here is
+        # for an unrelated boolean option that is using defaults (so
+        # will always work. It's a basic control that *anything* is working.
+        self.assertTrue(hasattr(self.conf, 'force_raw_images'))
+        self.assertTrue(hasattr(self.conf, 'reserved_huge_pages'),
+                        "Parse error with reserved_huge_pages")
+
+        # NOTE(sdague): Yes, this actually parses as an array holding
+        # a dict.
+        actual = [{'node': '0', 'size': '2048', 'count': '64'}]
+        self.assertEqual(actual, self.conf.reserved_huge_pages)